Rockwell Automation 1746-QV,D17466.18 OPEN-LOOP VELOCITY CONTL - Manual (Page 8)

1–2 System Overview
Publication 1746-6.18 April 1998
Because you can change the speed of the hydraulic ram with extend
and retract profiles and store additional profiles (recipes) in data
table iNteger (N) files, this control system has these benefits:
•
reduced cycle time – you can increase ram speed for faster operation
•
reduced or eliminated pressure spikes and water-hammering for
smoother operation and less wear and tear on the machine –
you can profile accelerations and decelerations of the hydraulic ram
•
energy savings – you can match the speed of the hydraulic pump
to the force that you need
•
faster new-part change-over – you can store your setups and
minimize mechanical re-adjustments between parts
The 1746-QV module executes the extend and retract profiles that you
load to control the motion of the hydraulic ram. You can program up
to seven different voltages over the length of travel in both the extend
and retract directions to control how the ram accelerates or decelerates.
V
oltage
Extend Direction
Position
V
oltage
Retract Direction
Segments Segments
Position LDT Head LDT Head
1
2
3
4
5
6
7 1
2
3
4
5
6
7
Each position setpoint triggers a corresponding voltage output in the
range of –10V to +10V dc that translates into speed. The LDT
provides high-speed position updates to the module for consistent and
repeatable motion.
Use the 1746-QV module in an SLC-based system for low-cost
control of:
•
hydraulic machinery
•
simple (non-CNC) hydraulic presses
•
diecasting machinery
•
welder placement
•
pneumatic actuators for clamping or placement
In addition, the module is designed to support standard proportional
amplifiers and retrofit into most existing hydraulic systems.
Why Use This System?
How Does It Work?
What Are Typical
Applications?